text: // Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
  //
  // Licensed under the Apache License, Version 2.0 (the "License");
  // you may not use this file except in compliance with the License.
  // You may obtain a copy of the License at
  
  //     http://www.apache.org/licenses/LICENSE-2.0
  //
  // Unless required by applicable law or agreed to in writing, software
  // distributed under the License is distributed on an "AS IS" BASIS,
  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  // See the License for the specific language governing permissions and
  // limitations under the License.
  
  #include <stdint.h>
  #include <string.h>
  #include <stdbool.h>
  #include "freertos/xtensa_api.h"
  #include "freertos/FreeRTOSConfig.h"
  #include "freertos/FreeRTOS.h"
  #include "freertos/queue.h"
  #include "freertos/task.h"
  #include "esp_log.h"
  #include "spp_task.h"
  
  static void spp_task_task_handler(void *arg);
  static bool spp_task_send_msg(spp_task_msg_t *msg);
  static void spp_task_work_dispatched(spp_task_msg_t *msg);
  
  static xQueueHandle spp_task_task_queue = NULL;
  static xTaskHandle spp_task_task_handle = NULL;
  
  bool spp_task_work_dispatch(spp_task_cb_t p_cback, uint16_t event, void *p_params, int param_len, spp_task_copy_cb_t p_copy_cback)
  {
      ESP_LOGD(SPP_TASK_TAG, "%s event 0x%x, param len %d", __func__, event, param_len);
  
      spp_task_msg_t msg;
      memset(&msg, 0, sizeof(spp_task_msg_t));
  
      msg.sig = SPP_TASK_SIG_WORK_DISPATCH;
      msg.event = event;
      msg.cb = p_cback;
  
      if (param_len == 0) {
          return spp_task_send_msg(&msg);
      } else if (p_params && param_len > 0) {
          if ((msg.param = malloc(param_len)) != NULL) {
              memcpy(msg.param, p_params, param_len);
              /* check if caller has provided a copy callback to do the deep copy */
              if (p_copy_cback) {
                  p_copy_cback(&msg, msg.param, p_params);
              }
              return spp_task_send_msg(&msg);
          }
      }
  
      return false;
  }
  
  static bool spp_task_send_msg(spp_task_msg_t *msg)
  {
      if (msg == NULL) {
          return false;
      }
  
      if (xQueueSend(spp_task_task_queue, msg, 10 / portTICK_RATE_MS) != pdTRUE) {
          ESP_LOGE(SPP_TASK_TAG, "%s xQueue send failed", __func__);
          return false;
      }
      return true;
  }
  
  static void spp_task_work_dispatched(spp_task_msg_t *msg)
  {
      if (msg->cb) {
          msg->cb(msg->event, msg->param);
      }
  }
  
  static void spp_task_task_handler(void *arg)
  {
      spp_task_msg_t msg;
      for (;;) {
          if (pdTRUE == xQueueReceive(spp_task_task_queue, &msg, (portTickType)portMAX_DELAY)) {
              ESP_LOGD(SPP_TASK_TAG, "%s, sig 0x%x, 0x%x", __func__, msg.sig, msg.event);
              switch (msg.sig) {
              case SPP_TASK_SIG_WORK_DISPATCH:
                  spp_task_work_dispatched(&msg);
                  break;
              default:
                  ESP_LOGW(SPP_TASK_TAG, "%s, unhandled sig: %d", __func__, msg.sig);
                  break;
              }
  
              if (msg.param) {
                  free(msg.param);
              }
          }
      }
  }
  
  void spp_task_task_start_up(void)
  {
      spp_task_task_queue = xQueueCreate(10, sizeof(spp_task_msg_t));
      xTaskCreate(spp_task_task_handler, "SPPAppT", 2048, NULL, 10, &spp_task_task_handle);
      return;
  }
  
  void spp_task_task_shut_down(void)
  {
      if (spp_task_task_handle) {
          vTaskDelete(spp_task_task_handle);
          spp_task_task_handle = NULL;
      }
      if (spp_task_task_queue) {
          vQueueDelete(spp_task_task_queue);
          spp_task_task_queue = NULL;
      }
  }
  
  void spp_wr_task_start_up(spp_wr_task_cb_t p_cback, int fd)
  {
      xTaskCreate(p_cback, "write_read", 2048, (void *)fd, 5, NULL);
  }
  void spp_wr_task_shut_down(void)
  {
      vTaskDelete(NULL);
  }